Anger. It’s thundering through the Conservative grassroots. Who do these MPs think they are? What right do they have to ride roughshod over their country, their party and their voters?

Since I set up my Stand Up For Brexit campaign, I have spoken to thousands of Conservative activists. Many were willing to cut the party leadership some slack. They were aggrieved that the 2017 election didn’t go as planned – almost certainly due to a hurriedly-devised manifesto which wasn’t properly road-tested. We were sad to see good, Brexit-supporting MPs like Stewart Jackson and David Nuttall lose their seats. But, ultimately, we believed that Theresa May would stick to her promises – her oft-quoted ‘red lines’ – and deliver Brexit.

How wrong we were. Theresa May’s decision in the last 48 hours to overrule her Cabinet and sub-contract Brexit to Jeremy Corbyn is an abomination. This is the man we have rightly said should be allowed nowhere near power; a Marxist terrorist-sympathiser, who has unleashed a plague of anti-Semitism on the Labour movement, the Jewish community and wider society. In her latest appalling decision (there have been many, but this is by far the worst), Theresa May has legitimised him. She has picked a side and, my goodness, she’s picked the wrong one.

Labour, naturally, will make hay with this. The hard-left views and activity of Jeremy Corbyn, John McDonnell and their top team have always been a problem to them. Voters were naturally suspicious. No matter how incompetent the Conservatives appeared, there was still a nagging doubt; a sense that Labour were not really in a place where they could be trusted with the country. Through the travails of Brexit, this was my party’s strongest card. Well, Theresa May has now taken that card and torn it into bits. I fear we shall rue the day.

For many Conservative activists, this was quite simply the final straw. 70% of the party membership and 70% of Conservative voters support Brexit. It’s very clear from the referendum that leaving the EU meant leaving the Single Market and Customs Union, as promised in the 2017 Conservative manifesto. As I write, Twitter is awash with photos of cut-up membership cards. Wealthier supporters have reduced or stopped their donations. Associations are seeing members down tools; individuals who would previously have jumped at the chance to be candidates are refusing to stand. The voluntary party is in meltdown. Indeed, it’s only residual loyalty to the Conservative brand, and the minority of backbenchers who have tried valiantly to deliver on their promises, which is preventing complete collapse.

Activism, as anyone who has campaigned for a political cause will know, is hard work. Long hours, delivering literature and engaging with people who don’t necessarily wish to be engaged with – all at your own expense. You do it to get people elected who believe in the same cause as you. If that MP – be it Dominic Grieve, Anna Soubry, Heidi Allen or any other – proceeds to reveal that they have no intention of keeping their key promise, it is a huge kick in the teeth. Despite the accusations to the contrary, Brexiteers have been forced to compromise repeatedly. “Plan A+” and “the Malthouse Compromise”, all have fallen on the deaf ears of a Prime Minister who sees Brexit as a bomb to be neutralised and a Parliament in which the majority – despite their protestations about honouring the result – wish to Remain.

Throughout all of this, CCHQ’s behaviour has been dreadful. Tin-eared and dictatorial. For nine months, members have been ignored and gaslighted. Now they’re being asked to row in meekly behind the complete betrayal of our manifesto – and, in this sudden appeal to Corbyn and his anti-Western Marxist agitators, betrayal of our shared conservative values too.

What a sad state of affairs. For the Tories, Brexit presented an historic opportunity to reconnect with the working-class vote which kept Margaret Thatcher in power and prove that we are not a party of the establishment, but a party of everyone. Instead, it finds itself gripped by an existential crisis – and Parliament in a self-indulgent, completely unnecessary deadlock.

Conservative Leavers, like all Leavers, are deeply frustrated and cross. But we must filter this energy into reform; of the party and the system – from the ground, up. Despite everything, our country still needs us. And it still needs Brexit.

It seems fair to say that the draft withdrawal agreement agreed between negotiators and published this week has not been universally welcomed. In particular the Protocol on Ireland/Northern Ireland has been the source of much criticism. In a detailed briefing by the Institute of Economic Affairs, I described how, if it were to come into effect, this Protocol would effectively rule out an independent trade policy for the UK, and would throw up serious trade barriers between Great Britain and Northern Ireland.

It’s worth reminding ourselves of why this Protocol was thought to be necessary. Our government agreed in December last year to guarantee that there would be no physical infrastructure or related checks and controls at the border between Ireland and Northern Ireland. In order to achieve this they conceded that, unless they could put forward alternative solutions, Northern Ireland would stay in alignment with the rules of the customs union and single market in all areas necessary for north south cooperation, the all-island economy and protection of the Belfast (“Good Friday”) Agreement. It was also stated in the Joint Report that the UK would not allow new regulatory barriers between Great Britain and the United Kingdom. The EU’s interpretation of that was a draft agreement under which, “unless and until” other terms were agreed that would meet the objectives for the Irish border, Northern Ireland would remain in a customs union and regulatory area with the EU. This is what the backstop is.

The facilitated customs arrangement and common rulebook of the Chequers plan were an attempt to provide the alternative arrangement that would mean the backstop would never be activated. When Chequers was roundly rejected by the EU, and the Prime Minister declared after the Salzburg summit that no prime minister could accept the EU’s terms, the negotiators went back into their tunnel and reformulated the backstop so that Northern Ireland and the rest of the UK would be in the same customs territory, and Northern Ireland would retain EU regulations on goods “unless and until” a new agreement could be reached. Mrs May is now satisfied that this is something that a British prime minister can sign up to.

Some of us have long been convinced that keeping the Irish border free of infrastructure could be achieved by way of legal, technical and technological solutions. European customs experts Hans Maessen and Lars Karlsson have confirmed to the Northern Ireland Affairs Committee that this can be done. But the EU negotiators and the Irish government have been adamant that the requirements of EU law mean that only a customs union and regulatory harmonisation on goods can achieve this, as even with a free trade agreement with zero tariffs and quotas, the risk of goods that have not been duly declared for customs purposes or that do not meet EU regulations might cross the border cannot be tolerated. Except, it now transpires, for fish. Because under article 6 of the Protocol, fisheries and aquaculture products will be excluded from the customs union arrangements (and therefore fish caught by British and Northern Irish boats would be subject to tariffs) unless an agreement between the UK and the EU on access to waters and fishing opportunities is reached. But by the EU’s own reasoning, the exclusion of even one product would require a full customs border, to ensure that that product isn’t smuggled in undeclared. Now Irish government and EU negotiators could be forgiven for assuming that the British negotiators will concede on this as they have on almost everything else, and sign away fishing rights to the EU. But they might not, and then we would need a hard border wouldn’t we, and the Protocol would be for nothing? Or could it be, that for fish, as for everything else, it is possible to manage a customs border without physical interventions, and the EU is prepared to take the risk of having to do so in order to leverage access to UK territorial waters.

It’s impossible to know for certain what deal the Prime Minister and her advisers are planning to spring on the Cabinet, Parliament and the country over the coming days; all that’s for sure is that they are, we are told, about to come up with something. The signals have, however, been clear enough, so that a pretty good guess can be made: their plan is to come up with a last-minute triumphant announcement that the ‘backstop’ problem on the Northern Ireland border issue has been resolved, and in the UK’s favour.

Whether they will be correct or not in announcing that is irrelevant; that’s what they’ll announce – and indeed, it is perfectly possible that some major concession will be offered up by the European Union on this point, since the border ‘problem’ was always a ruse, designed to focus attention on a non-problem while funnelling the negotiations into an agreement that would include membership of the Customs Union (and, to all intents and purposes, the Single Market). If the Northern Ireland border was a problem, then it could be resolved by us staying in the Customs Union; ergo, we agree to stay in the Customs Union thus ensuring that the Northern Ireland border is not a problem. Whatever the reason for the backstop imbroglio, it is in any event a chimera – something that has become, in the most ludicrous way, the tiny tail that wags the enormous dog of Brexit.

The border in Ireland already divides two jurisdictions with different tax regimes, products and the like. It should never have become an issue; the authorities on both sides already monitor it, to prevent smuggling, but through intelligence-led policing, not physical border structures. It is a border that the UK, the Irish and the EU have all confirmed will never be hard.

Now it has become a pretence for bouncing a post-Brexit UK into the Customs Union, complete with further surrenders on fishing and financial services. That reputable people apparently take the backstop issue seriously is a puzzle. The backstop is nonsense; both sides have repeatedly confirmed that they will not impose a hard border between Northern Ireland and the Republic of Ireland. The issues of wandering cows and travelling milk can be resolved through agreements on sanitary and phyto-sanitary standards, not through physical border impedimenta. The amount of trade involved is negligible. The issue is a fraud and should be treated as such.

Some assert that the Prime Minister is desperate to keep us in the Customs Union because of promises, never published, that Greg Clark made to the auto industry two years ago. Others point to paragraph 49 of the December agreement with the EU (where the backstop is promised). This ignores the next paragraph, paragraph 50, inserted at the insistence of the DUP, which basically negates any claim that paragraph 49 is binding. Regardless: the Prime Minister and her advisers’ major mistake seems to be that they believe that if victory can be declared regarding the backstop, they can then come back from Brussels, waving a piece of paper and asserting a good deal has been agreed, because the backstop has been resolved.

It won’t work. Way before backstop became the cause du jour of the negotiations, Chequers had already reared its ugly head, and Chequers is what this whole false angst about the Northern Ireland border has been about; to provide a reason for the UK to stay in the Customs Union after Brexit. Chequers is no good; enough people know it is no good; it won’t be possible.

There are many reasons why the UK must avoid at all costs being in the – or a – Customs Union.This article by Graham Gudgin published on BrexitCentral yesterday is a comprehensive tour d’horizon of these reasons. MPs – both Remainers and Brexiteers – understand all that, enough of them to preclude its being accepted by Parliament. And yet, when the Irish border “issue” has allegedly been put to bed, with some sort of faux “backstop” agreement, Chequers will, apparently, remain as the Government’s negotiating stand for Brexit: a proposal that we remain tightly bound into the Customs Union (and for all intents and purposes, the Single Market) – goods, fisheries, banking and all.

There have been some eyebrow-raising odd leaks from “EU officials” in recent weeks, claiming that the EU’s arm was being twisted to force them to graciously allow the UK to stay within the Customs Union. Some may find that a joke – since the UK in the Customs Union is, in theory, precisely that vassal status that the EU should want the UK to be in (i.e. having German goods and French produce stuffed down our throat, with no say in the rules that govern competition in such goods and produce).

Nonetheless, I’m told that M. Barnier has assured delegations from the UK, with the utmost sincerity, that he does not wish the UK to be in the Customs Union. That is, however, what looks like is being offered by the UK in return for a “solution” to the Irish border. It is, also, precisely where the Government’s fatal error lies: enough Members of Parliament have made it very clear that they are not going to vote for such a deal, so any deal built around a Chequers view of the world will fail in the so-called ‘Meaningful Vote’ that we expect to take place in the House of Commons in the coming weeks.

The Chequers construct involves keeping the UK within a Customs Union and (as the news from the City of London illustrates) also the Single Market – for an extended, possibly indefinite, quite possibly permanent, length of time. It has been identified over and over as something that a large group of MPs will not accept.

How many such MPs? Well, there are so far 51 who have signed up to the “Stand Up for Brexit” pledge; there is a handful of Labour Leaver MPs; there are 10 DUP MPs; there are the ten or so further Scottish Tory MPs from fishing communities who know it would be electoral suicide to vote with the Government on this; there are the Remain-backing Conservative MPs, such as Jo Johnson, who now recognise that Chequers means vassalage; and there are most likely several Cabinet Ministers who will finally vote with their conscience by resigning their post and then voting against the Government in the Meaningful Vote.

The Labour Party says it will not support the Government in the Meaningful Vote, and it cannot be imagined that there will be enough renegade Labour Remainer MPs prepared to support the Conservative Government to overcome this group of anti-Chequers MPs so the Government, with its thin majority, faces an anti-Chequers vote that in total adds up to 60; 90; maybe many more.

What will the Prime Minister do when the reality of this becomes clear? What will happen if and when a Meaningful Vote on a Chequers-based deal is lost? The most likely outcome of such an event has to be that we would shortly thereafter have a new Prime Minister. If not, and somehow – however unlikely that may be – she survived the defeat of her policy (perhaps by ditching her clique of hardcore Remainer advisers, just as she ditched Nick Timothy and Fiona Hill after the 2017 election fiasco), then she would have the same choice as a new Prime Minister would: either to hunker down and start properly preparing to leave the European Union on WTO terms on 29th March next year; or to seek some kind of unholy alliance in Parliament with the Labour Party that allowed her to sue for peace with the EU by asking for an extension (temporary or ongoing) of Article 50 – with all that implies for a never-ending failure of the UK to exit the EU

The former choice carries the possibility of some – but if truth be told, not a lot – short-term pain, with a saving of £39 billion (enough to fund roughly 20,000 policemen and 20,000 teachers and 20,000 nurses for the next 20 years); the latter would rent the Conservative Party (the vast majority of whose voters side with the “Stand Up for Brexit” MPs) in two, with disastrous likely consequences in 2022. The Conservative Party might not recover for a generation or more.

It is late – very late – but the Government must urgently reconsider its position, and move to, first, making clear that a WTO terms exit is very much in contemplation, and second, offering as an alternative to that a Canada-style deal with the EU, as described in Plan A+ – a clearly laid out and workable plan for a Free Trade Agreement that builds on the already solid work that David Davis and Steve Baker did while still in Government.

The EU has indicated it is prepared to accept such a deal; it is the only deal that can pass a Meaningful Vote in the Commons; it is extraordinary that the Government has not already pivoted to such a deal. Anything else, and the current shambles will just get even worse: if and when Chequers comes to the Commons, it will be defeated and the Government, as currently led, will fall.